Patroni: Update reference architecture documentation for patroni

What does this MR do?

• Make any Patroni related changed to the reference architecture
• Modifies any references for roles ['something'] to roles(['something']) (our roles syntax require space, which is confusing, because it's a method call... the new format make it less confusing and less prone to error)
• Removed redundant flags that are enabled/disabled based on the role being used

Related issues

Closes #329533 (closed)

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When applicable:

• Update the permissions table.
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• Add/update the feature flag section.

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